Week #8
Chemistry 21b Spectroscopy & Statistical Thermodynamics
Supplemental Notes Photoelectron and Related Spectroscopies
When photons of suciently short wavelength interact with molecules, ionization can
result. The free electrons that are produced can
Chemistry 21b Winter 2011
Midterm Solution Set
T.A.s Scarlett Dong, Jason Crowley
1. (a) This was hopefully a straightforward question. The ml and ms ranges give you 2L+1
and 2S+1 values by spanning from (-L,-S) to (L,S) in integer steps, so the independe
Chemistry 21b
Midterm Examination
Out: 04 February 2011
Due: 10 February 2011
This is an open book, and closed web, examination. So, you may use the texts along
with the posted Lecture Notes and Problem Sets (with Solutions), but no browsing. In
particula
09March2011
Chemistry 21b Spectroscopy
Lecture # 27 Electron Spin Resonance Spectroscopy
Like the hydrogen nucleus, an unpaired electron in a sample has a spin of I=1/2. The
magnetic dipole moment of this unpaired electron, B , is thus equal to
B
= ge
e
I
07Mar2011
Chemistry 21b Spectroscopy
Lecture # 26 Fourier Transform & Multi-Dimensional NMR
For the simple NMR spectra discussed in Lecture 25, one means of recording the
chemical shift spectrum is to sweep the static magnetic eld strength B0 across each
04Mar2011
Chemistry 21b Spectroscopy
Lecture # 25 Nuclear Magnetic Resonance Spectroscopy
Along with infrared spectroscopy, nuclear magnetic resonance (NMR) is the most
important method available for the determination of molecular structure particularly f
28Feb2011
Chemistry 21b Spectroscopy
Lecture # 23 Electronic Spectroscopy and Non-Radiative Processes
As was noted briey in Lecture #20, the ultraviolet spectroscopy of formaldehyde
(specically the and n transitions) is complicated by the fact that at 3 e
25Feb2011
Chemistry 21b Spectroscopy
Lecture # 22 Electronic Spectroscopy of Periodic Solids
Previously we have investigated the vibrational modes of periodic solids using the
harmonic potential approximation. Here we are interested in the electronic prop
18Feb2011
Chemistry 21b Spectroscopy
Lecture #20 Electronic Spectroscopy of Simple Polyatomic Molecules
The electronic spectra of polyatomic molecules can become hopelessly congested at
high resolution because of the very high density of eigenstates. Furt
16Feb2011
Chemistry 21b Spectroscopy
Lecture # 19 Photodissociation Processes & the Reection Approximation
In any environment or experiment where ultraviolet photons are present,
photodissociation, typically depicted as
XY + h
X+Y
,
(19.1)
must be conside
14Feb2011
Chemistry 21b Spectroscopy
Lecture # 18 Diatomic Bonding/Electronic Structure
& the Franck-Condon Approximation
As well described in Chapter 11 of McQuarrie, for diatomics heavier than H2 , we start
with the simplest implementation of LCAO-MO de
11Feb2011
Chemistry 21b Spectroscopy
Lectures # 17 The Vibrational Modes of Periodic Solids
In the infrared spectra of functional groups we covered last time, we saw that for
so-called molecular solids (or liquids) in which the interactions between molecu
09Feb2011
Chemistry 21b Spectroscopy
Lecture # 16 Local Mode Theory & The Vibrations of Functional Groups
Despite the general success of normal mode theory in the analysis of polyatomic
molecule vibrational spectra, there are several experiments that are
07Feb2011
Chemistry 21b Spectroscopy
Lecture # 15 The Raman Eect & Rovibrational Band Structure
Although the Raman eect has been known of for over fty years, its employment as a
routine spectroscopic method was quite limited until the development of high
04Feb2011
Chemistry 21b Spectroscopy
Lecture # 14 The Quantum & Group Theoretical Treatment of Molecular Vibrations
The classical normal mode solution derived in Lecture #13 provides a very
straightforward quantum mechanical generalization of the one-dime
02Feb2011
Chemistry 21b Spectroscopy
Lecture # 13 The Classical Treatment of Molecular Vibrations
For a gas phase molecule with N atoms, there will be a total of 3N degrees of freedom
in free space. Three of these will be involved in translation, which ma
31Jan2011
Chemistry 21b Spectroscopy
Lecture # 12 Group Theory in Spectroscopy
Molecular symmetry is the unifying thread throughout spectroscopy and molecular
structure theory. It makes it possible to classify states, and, more importantly, to determine
s
28Jan2011
Chemistry 21b Spectroscopy
Lecture # 11 Vibration-Rotation Spectra of Diatomic Molecules
What happens to the rotation and vibration spectra of diatomic molecules if more
realistic potentials are used to describe the interatomic interaction? So f
26Jan2011
Chemistry 21b Spectroscopy
Lecture # 10 Rotation of Asymmetric Tops & Centrifugal Distortion
Most molecules are asymmetric tops, which means that Ia = Ib = Ic . Thus, the
rotational Hamiltonian
2
J2
J2
1 Ja
(10.1)
+ b+ c
H rot =
2 Ia
Ib
Ic
canno
24Jan2011
Chemistry 21b Spectroscopy
Lecture # 9 Rotation of Polyatomic Molecules
The rotational spectra of molecules can be classied according to their principal
moments of inertia. Assume that the molecule rotates as a rigid body, that is, the
relative
21Jan2011
Chemistry 21b Spectroscopy
Lecture # 8 Spectroscopic Line Shapes
Now that we have established the strength and time-dependence of the interaction
of light with matter, the last general set of trends we will need to think about before
beginning a
19Jan2011
Chemistry 21b Spectroscopy
Lecture # 7 Time-Dependent Perturbation Theory & Light-Matter Interactions
In Ch 21a you considered the eects of small, time independent perturbations to
various systems (see also the supplemental notes from Week #1).
14Jan2011
Chemistry 21b Spectroscopy
Lecture # 6 Nuclear Motion in Diatomic Rotors
Once the electronic potential energy surfaces have been computed the motion of the
nuclei can be determined by solving eq. (4.10). Here for simplicity we will consider the
12Jan2011
Chemistry 21b Spectroscopy
Lecture # 5 MO Theory for & H2 , Electronic Nomenclature for Molecules
1. The Chemical Bond & Molecular Hydrogen
Recall that the polyatomic Hamiltonian is:
H
where
VNe =
,i
= TN + Te + VNe + Vee + VNN
TN =
(5.1)
TN
10Jan2011
Chemistry 21b Spectroscopy
Lecture # 4 The Born-Oppenheimer Approximation, H+
2
1. Born-Oppenheimer approximation
As for atoms, all information about a molecule is contained in the wave function ,
which is the solution of the time-independent Sc
Chemistry 21b
Final Examination
Out: 11 March 2011
Due: 16 March 2011, 5 pm
This is an open book examination, and so you may use McQuarrie or Harris and
Bertolucci along with the posted Lecture Notes and Problem Sets (with Solutions). Use of
a calculator
INSTITUTE OF PHYSICS PUBLISHING J. Phys.: Condens. Matter 17 (2005) S1459S1469
JOURNAL OF PHYSICS: CONDENSED MATTER doi:10.1088/0953-8984/17/18/004
Site directed spin labelling and pulsed dipolar electron paramagnetic resonance (double electronelectron re
03-07Jan2011
Chemistry 21b Molecular Structure & Spectroscopy
Week # 1 Supplemental Notes Perturbation Theory
Perturbation Theory in Quantum Mechanics
Before we launch into a detailed investigation of the ways in which molecules, liquids,
and solids inter
03-07Jan2011
Chemistry 21b Molecular Structure & Spectroscopy
Week # 1 The Electronic Structure of Atoms
In this quarter of Ch21, we will be primarily concerned with spectroscopy the
interaction of light with matter and what it can tell us about molecules